Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758064AbbGHTAn (ORCPT ); Wed, 8 Jul 2015 15:00:43 -0400 Received: from mail-wi0-f173.google.com ([209.85.212.173]:32961 "EHLO mail-wi0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751479AbbGHTAf (ORCPT ); Wed, 8 Jul 2015 15:00:35 -0400 Date: Wed, 8 Jul 2015 21:00:30 +0200 From: Ingo Molnar To: Linus Torvalds Cc: Shuah Khan , Ming Lei , Greg Kroah-Hartman , Linux Kernel Mailing List , Shuah Khan Subject: Re: Linux 4.2-rc1 Message-ID: <20150708190030.GA26346@gmail.com> References:

MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4397 Lines: 94 * Linus Torvalds wrote: > On Wed, Jul 8, 2015 at 9:32 AM, Shuah Khan wrote: > > > > I am seeing the following NULL pointer dereference on my test system: > > > > [ 3.640599] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 > > [ 3.640609] IP: [] firmware_uevent+0x23/0x80 > > Decoding the "Code:" line shows that this is the "->fw_id" dereference in > > if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id)) > return -ENOMEM; > > and that "fw_priv->buf" pointer is NULL. > > However, I don't see anything that looks like it should have changed > any of this since 4.1. > > Adding the appropriate firmware people to the cc. Btw., FWIW, a couple of days ago I started seeing a similar crash pattern when I updated my randconfig testing system to v4.2-rc1: cfg80211: Kicking the queue cfg80211: Exceeded CRDA call max attempts. Not calling CRDA BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 IP: [] firmware_uevent+0x1a/0xae PGD 0 Oops: 0000 [#1] SMP CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.2.0-rc1-01514-g4a704ed-dirty #411 Hardware name: System manufacturer System Product Name/A8N-E, BIOS ASUS A8N-E ACPI BIOS Revision 1008 08/22/2005 task: ffff88003d4f0000 ti: ffff88003d4f8000 task.ti: ffff88003d4f8000 RIP: 0010:[] [] firmware_uevent+0x1a/0xae RSP: 0018:ffff88003d4fba38 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff88003ac05668 RCX: 0000000000000003 RDX: 0000000000000001 RSI: ffffffff83822d1a RDI: ffff88003ac05668 RBP: ffff88003ae68008 R08: 000000003ac057f4 R09: 000000010013ffff R10: ffffffffffffffff R11: ffffffff84f831e0 R12: ffff88003ae68018 R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff838947a7 FS: 0000000000000000(0000) GS:ffff88003fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000080 CR3: 0000000003a50000 CR4: 00000000000006a0 Stack: 0000000000000003 ffff88003ac05668 ffff88003ae68008 ffffffff81b4a0fa ffff88003d50e1a8 00000000fffffffe ffffffff838947a7 0000000000000002 000000003ac057e1 ffff88003ac05668 ffff88003ae68018 ffffffff831606f0 Call Trace: [] ? dev_uevent+0x284/0x312 [] ? kobject_uevent_env+0x304/0x54b [] ? do_raw_spin_lock+0x30/0x5e [] ? device_del+0x287/0x2c5 [] ? _request_firmware+0x71b/0xca2 [] ? r100_cp_init+0x254/0x692 [] ? r300_startup.constprop.0+0x2da/0x36b [] ? r300_init+0x2e9/0x3a9 [] ? radeon_device_init+0xbf1/0xe95 [] ? radeon_driver_load_kms+0x10f/0x24c [] ? drm_dev_register+0xec/0x19b [] ? drm_get_pci_dev+0x1d0/0x2d2 [] ? local_pci_probe+0x34/0xa2 [] ? pci_device_probe+0x131/0x187 [] ? driver_probe_device+0x160/0x3a8 [] ? __driver_attach+0x9e/0xd4 [] ? driver_probe_device+0x3a8/0x3a8 [] ? bus_for_each_dev+0x89/0x9b [] ? bus_add_driver+0x151/0x2ee [] ? driver_register+0xe8/0x147 [] ? r128_init+0x1f/0x1f [] ? do_one_initcall+0x11e/0x25b [] ? parse_args+0x327/0x414 [] ? kernel_init_freeable+0x11a/0x1dc [] ? initcall_blacklist+0xc1/0xc1 [] ? rest_init+0x75/0x75 [] ? kernel_init+0x6/0x14c [] ? ret_from_fork+0x3f/0x70 [] ? rest_init+0x75/0x75 Code: c7 c6 3d 7f 80 83 31 c0 e8 f3 c8 bc ff 5a 48 98 c3 55 48 89 fd 53 48 89 f3 48 c7 c6 1a 2d 82 83 51 48 8b 87 90 02 00 00 48 89 df <48> 8b 90 80 00 00 00 31 c0 e8 c9 2f bc ff 85 c0 0f 95 c0 0f b6 RIP [] firmware_uevent+0x1a/0xae RSP CR2: 0000000000000080 ---[ end trace 3ab09bb9b953b39a ]--- Haven't had the time to dig into it yet. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/